How A Repair Protein Looks For DNA Damage

A repair protein that looks for damaged DNA has been found that could possibly be used later on for treatments. (Photo : Plethrons/YouTube)

DNA damage can be caused by a number of factors. DNA damage could also result into a number of diseases later in life. Scientists are looking for ways to repair DNA that might possibly be damaged, and a protein might just be the one that scientists are looking for.

Rad4 is a protein that is essential for DNA repair and researchers from the University of Pittsburgh School of Medicine and University of Pittsburgh Cancer Institute have noted how the protein works. Rad4 scans DNA in a way called constrained motion, wherein in finds structural faults in DNA, as Science Daily reports.

While Rad4 can help in DNA repair, it could also be mutated in humans. Its mutated variant is called XPC and along with other mutated repair proteins, it could cause a condition called xeroderma pigmentosum. This condition makes a person sensitive to sunlight and could have a high risk of developing skin cancer, as Medical Express notes.

To study how Rad4 acts, Muwen Kong, one of the participants in the study, have both normal and mutant Rad4 tagged. Light-emitting quantum dots were used to tag the proteins. The researchers then looked to see how Rad4 moves on DNA through a fluorescence microscope.

Rad4, together with another repair protein, Rad23, is first to arrive and then scans the DNA. Scanning is done by bending the damaged DNA. DNA whose structure has been altered is much harder to bend. The protein then goes into a constrained motion pattern so that it can look into the damaged portion more closely. After scanning it Rad4 then calls out, as it is, other proteins that would then complete DNA repair.

New treatments could be made based on the results of the study. This might be used later on in treating such diseases as cancer. Having Rad4 and other repair proteins as a base ingredient, new treatments then could be made and used together with treatments already in place. Earlier it has been reported that smoking can cause DNA damage, and the new research could help in that area as well.

Dr. Bennett Van Houten is the lead author of the study along with Richard M. Cyert, Professor of Molecular Oncology at the Pittsburgh University School of Medicine and co-leader of UPCI's Molecular and Cellular Cancer Biology Program.